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991.
Gary D. Schnell Ana E. Hiott J. Curtis Creighton Victoria L. Smyth April Komendat 《Journal of Insect Conservation》2008,12(5):483-492
The endangered American burying beetle (Nicrophorus americanus) is relatively abundant at Fort Chaffee Maneuver Training Center in northwestern Arkansas. There is a paucity of basic life-history
information available, particularly with respect to factors affecting overwintering success. In a field experiment we: (1)
captured beetles at Fort Chaffee; (2) bred them in captivity; (3) in the fall on Fort Chaffee placed offspring individually
in well-ventilated, lidded 21.1-l buckets containing original soil plugs in grassland or woodland, either provisioned or not
with a rat carcass as potential food; (4) overwintered the beetles; (5) checked in the spring to determine survival; and (6)
released surviving beetles. Overall, 59.6% of 104 beetles survived the winter, with 77.1% and 44.6% survival in provisioned
and nonprovisioned buckets, respectively. No differences were evident between habitats. Beetle age was an important survival
predictor, with older beetles having a higher survival probability, but only if nonprovisioned. Gender and body size were
not predictive of survival. Many surviving beetles were at or near the surface; depth averaged 6.0 cm, with some as deep as
20 cm. Our findings suggest that American burying beetles will have a higher probability of overwinter survival if carcasses
are readily available as winter approaches. 相似文献
992.
ELILDO ALVES RIBEIRO CARVALHO JR ALBERTINA PIMENTEL LIMA WILLIAM ERNEST MAGNUSSON ANA LUISA KERTI MANGABEIRA ALBERNAZ 《Austral ecology》2008,33(6):723-729
Abstract We investigated the effect of forest fragmentation on the abundance of the gekkonid lizards Coleodactylus amazonicus and Gonatodes humeralis in fragments associated with Amazonian savanna near Alter do Chão, Pará, Brazil. These fragments have been isolated for at least 150 years and probably more. Abundance of lizards, tree density and food availability were estimated in 1000‐m transects in eight sites in continuous forest and 21 forest fragments, ranging in size from 3.6 to 360 ha and distant from ~150–10 000 m from continuous forests. Coleodactylus amazonicus was at least an order of magnitude more adundant than G. humeralis in continuous forest, and both species were negatively affected by fragmentation. Coleodactylus amazonicus was encountered only in continuous forest, the largest fragment, and one fragment adjacent to continuous forest. Gonatodes humeralis occurred in the majority of fragments, but was more common in continuous forest, and occurred in lower densities in fragments more distant from continous forest. The species with lowest recorded densities in continuous forest was the most resistant to fragmentation, contrary to what would be predicted from neutral models, such as island‐biogeography theory, possibly because other factors are more important than initial population size in long‐term fragmented landscapes. 相似文献
993.
Ocaña-de Jesús RL AT Gutiérrez-Ibáñez JR Sánchez-Pale MD Mariezcurrena-Berasain G Velázquez-Garduño A Laguna Cerda I Rojas Puebla 《Phyton》2015,84(1):45-50
The aim of the current research was to determine tomato (Solanum lycopersicum L.) microbiological quality produced under greenhouse conditions in 5 municipalities of the State of Mexico. Studies were conducted during the 2013 production cycle to know the risks and apply prevention strategies prior to its consumption. A microbiological analysis of samples of irrigation water, soil and 100 tomato fruits variety cid was performed to determine Aerobic Mesophiles, Total Coliforms and Fecal Coliforms. The methodology used were those according to the Official Mexican Standards NOM- 109-SSA1-1994, NOM-110-SSA1-1994, NOM-092-SSA1-1994, NOM-113-SSA1-1994, and the Regulations of the National French Organization for Standardization (AFNOR) NF V08-60, and NOM-093-SSA1-1994, which establish the allowable limits for the study microorganisms. The results showed a zero level of pollution in water and soil samples. For fruits, levels of Aerobic Mesophilic were within the maximum limits permitted by the standards. The municipality of Texcaltitlan showed the highest average for these microorganisms (10083.80 CFU/mL). Huixquilucan showed 2266.84 CFU/mL for Total Coliforms. For Fecal Coliforms, municipalities of Coatepec and Texcaltitlan exceeded the allowed limit. 相似文献
994.
JOHN J. MACIEJEWSKI EMANUEL J. VACCHIANO SUZANNE M. MCCUTCHEON HOWARD E. BUHSE JR. 《The Journal of eukaryotic microbiology》1999,46(2):165-173
The stalked, ciliated protozoan Vorticella convallaria possesses a highly contractile cytoskeleton consisting of spasmonemes and myonemes. The major component of these contractile organelles is the calcium-binding protein(s) called spasmin. Cloning and characterization of spasmin would help elucidate this contractile system. Therefore, enriched spasmoneme protein preparations from these contractile stalks were used to produce a monoclonal antibody to spasmin. A monoclonal antibody, 1F5, was obtained that immunolocalized specifically to the spasmonemes and the myonemes and recognized a 20-kD calcium-binding protein in spasmoneme protein preparations. A putative spasmin cDNA was obtained from a V. convallaria cDNA library and the derived amino acid sequence of this cDNA revealed an acidic, 20-kD protein with calcium-binding helix-loop-helix domains. The physical properties of the putative spasmin were assessed by characterization of a recombinantly-produced spasmin protein. The recombinant spasmin protein was shown to bind calcium using calcium gel-shift assays and was recognized by the anti-spasmin antibody. Therefore, a V. convallaria spasmin was cloned and shown to be a member of the EF-hand superfamily of calcium-binding proteins. 相似文献
995.
Labruna MB Jorge RS Sana DA Jácomo AT Kashivakura CK Furtado MM Ferro C Perez SA Silveira L Santos TS Marques SR Morato RG Nava A Adania CH Teixeira RH Gomes AA Conforti VA Azevedo FC Prada CS Silva JC Batista AF Marvulo MF Morato RL Alho CJ Pinter A Ferreira PM Ferreira F Barros-Battesti DM 《Experimental & applied acarology》2005,36(1-2):149-163
The present study reports field data of ticks infesting wild carnivores captured from July 1998 to September 2004 in Brazil. Additional data were obtained from one tick collection and from previous published data of ticks on carnivores in Brazil. During field work, a total of 3437 ticks were collected from 89 Cerdocyon thous (crab-eating-fox), 58 Chrysocyon brachyurus (maned-wolf), 30 Puma concolor (puma), 26 Panthera onca (jaguar), 12 Procyon cancrivorus (crab-eating-raccoon), 4 Speothos venaticus (bush-dog), 6 Pseudalopex vetulus (hoary-fox), 6 Nasua nasua (coati), 6 Leopardus pardalis (ocelot), 2 Leopardus tigrinus (oncilla), 1 Leopardus wiedii (margay), 1 Herpailurus yagouaroundi (jaguarundi), 1 Oncifelis colocolo (pampas-cat), 1 Eira barbara (tayara), 1 Galictis vittata (grison), 1 Lontra longicaudis (neotropical-otter), and 1 Potus flavus (kinkajou). Data obtained from the Acari Collection IBSP included a total of 381 tick specimens collected on 13 C. thous, 8 C. brachyurus, 3 P. concolor, 10 P. onca, 3 P. cancrivorus, 4 N. nasua, 1 L. pardalis, 1 L. wiedii, 4 H. yagouaroundi, 1 Galictis cuja (lesser grison), and 1 L. longicaudis. The only tick infested-carnivore species previously reported in Brazil, for which we do not present any field data are Pseudalopex gymnocercus (pampas fox), Conepatus chinga (Molina’s hog-nosed skunk), and Conepatus semistriatus (striped hog-nosed skunk). We report the first tick records in Brazil on two Felidae species (O. colocolo, H. yagouaroundi), two Canidae species (P. vetulus, S. venaticus), one Procyonidae species (P. flavus) and one Mustelidae (E. barbara). Tick infestation remains unreported for 5 of the 26 Carnivora species native in Brazil: Oncifelis geoffroyi (Geoffroy’s cat), Atelocynus microtis (short-eared dog), Pteronura brasiliensis (giant otter), Mustela africana (Amazon weasel), and Bassaricyon gabbii (olingo). Our field data comprise 16 tick species represented by the genera Amblyomma (12 species), Ixodes (1 species), Dermacentor (1 species), Rhipicephalus (1 species), and Boophilus (1 species). Additional 5 tick species (3 Amblyomma species and 1 species from each of the genera Ixodes and Ornithodoros) were reported in the literature. The most common ticks on Carnivora hosts were Amblyomma ovale (found on 14 host species), Amblyomma cajennense (10 species), Amblyomma aureolatum (10 species), Amblyomma tigrinum (7 species), Amblyomma parvum (7 species), and Boophilus microplus (7 species).This revised version was published online in September 2005 with corrected page numbers. 相似文献
996.
Matrix metalloproteinases (MMPs) are endopeptidases considered to be important regulators of the microenvironment of cancer. While MMPs are traditionally associated with the extracellular matrix (ECM), here we provide new evidence from an analysis of gene expression profiles from human tumor tissue that MMP-9 (gelatinase B) is associated with elements of the immune system in a way analogous to the association of other MMPs, such as MMP-2 (gelatinase A), with components of the ECM. An analysis of three independent microarray datasets of lung adenocarcinomas from previous studies [Nat. Med. 8, 816-824 (2002); Proc. Natl. Acad. Sci. USA 98, 13790-13795 (2001); Proc. Natl. Acad. Sci. USA, 98, 13784-13789 (2001)] showed that, in each dataset, out of the set of genes with significant correlations in mRNA expression to the expression of MMP9 (P < 0.005), a highly disproportionate number were found to be annotated in the Locuslink database as having a role in the anti-pathogen response. By comparison, out of the set of genes significantly correlated with the expression of MMP2, a highly disproportionate number were known components of the ECM. The same patterns observed in the lung data for both MMP2 and MMP9 were found as well in an additional published dataset of colon and ovarian adenocarcinomas [Am. J. Pathol. 159, 1231-1238 (2001)]. The results of this study suggest a greater functional role for MMP-9 in the immune response to cancer than what may previously have been thought. 相似文献
997.
Creighton CJ Ramabadran K Ciccone PE Liu J Orsini MJ Reitz AB 《Bioorganic & medicinal chemistry letters》2004,14(15):4083-4085
The major human metabolite of atomoxetine (4-hydroxyatomoxetine) was tested against a panel of receptors and enzymes, and was found to interact with the mu, delta, and kappa-opioid receptors based upon studies involving both binding and functional assays. 4-hydroxyatomoxetine was determined to be a partial agonist of the kappa-opioid receptor. 相似文献
998.
Design, synthesis, and conformational analysis of eight-membered cyclic peptidomimetics prepared using ring closing metathesis 总被引:1,自引:0,他引:1
As part of a program to identify novel scaffolds that adopt defined secondary structure when incorporated into peptides, we have designed and prepared a library of constrained eight-membered ring lactams based upon 7-amino-8-oxo-1,2,3,6,7-pentahydroazocine-2-carboxylic acid. Ring closing metathesis (RCM) was employed as the key step, proceeding in high yields to afford the Z olefin. In this reaction sequence, the first generation benzylidene ruthenium RCM catalyst was superior to the second-generation imidazoline catalyst, which gave extensive oligomerization at higher concentrations. Conformational analysis of the 2S,7S and 2R,7S stereoisomers revealed that the 2R,7S isomer is a Type VIa beta-turn in the solid state (X-ray crystal structure) and in water (NMR analysis). The Type VIa beta-turn is relatively rare, typically bearing the cis amide bond found in proline-containing sequences. The 2S,7S diastereomer has an extended geometry of the pendent amide chains. The corresponding saturated derivatives (7-amino-8-oxoazocane-2-carboxylic acid) were also synthesized and investigated. The 2S,7S azocane bears an extended geometry and mimics the C(+) conformer of ox-[Cys-Cys], found in a variety of naturally occurring peptides. The scaffolds described here are useful for the design of constrained peptidomimics with defined secondary structure. 相似文献
999.
Stadler P Feldmann HJ Creighton C Zeilhoffer HF Zimmermann V Schmitt M Molls M 《The International journal of biological markers》2000,15(3):235-236
Hypoxic tumors of patients with squamous cell carcinoma of the head and neck show a consistent trend towards poor treatment outcome. We now report that tumor hypoxia in these patients is correlated with elevated antigen content of the tumor-associated serine protease uPA (urokinase-type plasminogen activator), a marker of tumor cell invasion and metastasis. 相似文献
1000.
Skull Wars: Kennewick Man, Archaeology, and the Battle for Identity. David Hurst Thomas. New York: Basic Books, 2000. 326 pp.
Riddle of the Bones: Politics, Science, Race, and the Story of Kennewick Man. Roger Downey. New York: Copernicus, 2000. 202 pp. 相似文献
Riddle of the Bones: Politics, Science, Race, and the Story of Kennewick Man. Roger Downey. New York: Copernicus, 2000. 202 pp. 相似文献